Power generation facilities can be configured to deliver various grid services for revenue generation. For instance, power generations systems, such as renewable energy plants, can be configured to respond to requests for grid services, such as peak shaving, frequency response, ramp rate control, purchasing and selling of energy, load following, energy arbitrage, and other grid services. Typically, power generation facilities provide grid services in modal fashion such that the power generation facility responds to power demands for a single grid service at a time. Energy storage systems have become increasingly used to deliver power to utility grids either as part of standalone energy storage systems or as part of a renewable energy farm (e.g., a wind farm or solar farm) with an integrated energy storage system. Energy storage systems can include one or more battery banks or other energy storage devices that can be coupled to the grid via a suitable power converter. Energy storage systems are unique in that energy storage systems have the ability to both deliver and reserve energy for particular grid services.